For example, a Li ion battery is. known as a high-voltage and high-energy density battery. The Li ion battery is a cation-based battery utilizing a reaction between a Li ion and a cathode active material and a reaction between a Li ion and an anode active material. On the other hand, a fluoride ion battery utilizing a reaction of a fluoride ion is known as an anion-based battery.
For example, in Patent Literature 1, an electrochemical cell (a fluoride ion battery) provided with a cathode, an anode and an electrolyte capable of conducting an anion charge carrier (F−) is disclosed. Also, in paragraph [0021] of Patent Literature 1, it is disclosed that the electrolyte contains a solvent and a fluoride salt, which is MFn (M is alkali metals such as Na, K and Rb, or alkaline earth metals such as Mg, Ca and Sr). Also, in paragraph [0030] of Patent Literature 1, various compounds such as carbonates are disclosed as the solvent.